Your eyes have become super dry and irritated, and it hurts to move them. Or they are red, watery and swollen. Perhaps you have encountered all of the above. You may have noticed that your eyes look more bulging than before. In recent photos, you always seem to look surprised. Maybe you even had blurry or double vision. You know it’s not allergies, but you can’t figure out what’s going on.
You may have thyroid eye disease. And if you have an autoimmune thyroid disease, especially Graves’ disease, it’s even more likely. In fact, about 90 percent of cases of thyroid eye disease are seen in people with Graves’ disease, says Christian Nasr, MD, endocrinologist and medical director of the Cleveland Clinic’s Thyroid Center.
What is thyroid eye disease?
Thyroid eye disease (TED) is a rare autoimmune disease that affects the eyes. PDD causes swelling, inflammation, and damage in the muscles and tissues around the eyes. “The majority of cases are mild,” says Raymond Douglas, MD, PhD, an oculoplastic and orbital surgeon practicing in Beverly Hills and director of the thyroid eye disease program at Cedars-Sinai in Los Angeles.
Symptoms can vary, but they include:
- Pain behind the eyes
- Eyelid retraction (when your eyelid does not close completely)
- Bulging eyes
- Feel there’s something in your eyes
- Blurry vision
- Double vision
- Bloodshot eyes
- swelling of the eyelids
- Constant eye watering
- Pressure or pain in the eye socket
Who receives TED?
PDD usually occurs in people with Graves’ disease. Graves’ disease causes your thyroid to produce too much thyroid hormone, a condition called hyperthyroidism. “About half of patients with Graves’ disease will develop thyroid eye disease,” says Nasr. He adds that most cases of PDD occur within a year to 18 months after the development of Graves’ disease.
About 80% of people who come with TED have already been diagnosed with Graves’ disease, Douglas says. About 10% are diagnosed with PDD before Graves. Another 5% of PDD cases involve people with Hashimoto’s disease, Nasr says. In this condition, your thyroid does not produce enough thyroid hormone, a condition known as hypothyroidism. Although it’s rare, Douglas says some people with ASD don’t have a thyroid problem at all.
Thyroid eye disease is more common in women than in men. But when men develop PDD, it tends to be more serious. Douglas says cases of PDD peak around age 40-50 and again around age 60.
What is the link between PDD and hyperthyroidism?
Three conditions can cause hyperthyroidism. One is Graves’ disease, the most common. The others are thyroid nodules and toxic multinodular goiters. “Graves’ disease is the only condition where you can see thyroid eye disease associated with elevated thyroid hormone levels,” says Nasr.
Thyroid eye disease and hyperthyroidism are disorders of the immune system. “From what we know, there are two receivers that seem to be the culprit,” Douglas says. One is the thyrotropin (TSH) receptor, which is found primarily on thyroid cells. The other is the insulin-like growth factor receptor (IGF-1), which is found primarily on cells around the eyes. These two receptors sit next to each other, he says, and appear to be linked.
Experts don’t understand why, but the immune system begins to attack these receptors. When it attacks the TSH receptor, it causes too much thyroid hormone. “It’s like turning the thermostat up too high,” says Douglas. When the immune system attacks the IGF-1 receptor, it increases the amount of IGF-1. Cells around the eyes grow, divide and accumulate additional scar tissue, causing thyroid eye disease.
If you have Graves’ disease, certain things can increase your risk of developing thyroid eye disease. These include:
- Have a family history of PDD
- Be a woman
- Get radioactive iodine treatment
- Advanced age
- poorly controlled thyroid
What are the complications of TED?
PDD can affect the two most important parts of the eye: the cornea and the optic nerve. “We make sure that both of these things are monitored,” Nasr says.
Some of the possible complications that TED can cause include:
- Bulging eyes
- scratched cornea
- Extreme drought
- severe headaches
- blinking problem
- The eyelids do not close completely
- Restricted eye movement
- Double vision
- Increased pressure in the eyes
- Blindness (rare)
Nasr tells his patients to call immediately if they see a dark spot in their field of vision or several bright lights go off and on. This could indicate an optic nerve injury.
He says it’s also important to call right away if you experience severe pain or severe redness around your iris (the colored part of your eye). It could mean that your cornea is damaged.
Who treats TED?
Both doctors say treating thyroid eye disease involves an integrative approach. Experts on your care team may include:
- Oculoplastic surgeons
“It’s really a team approach between mostly endocrinologists and oculoplastic surgeons,” says Douglas. Many people start by seeing their eye doctor to figure out what’s going on. “Then, depending on the severity, they will be sent to someone like me, an oculoplastic surgeon, who will then talk to them about medical therapies versus surgical therapies,” he says.
Many general ophthalmologists are also comfortable monitoring mild PDD, Nasr says. They can track your eye pressure, check your corneas, and do tests to make sure your optic nerve is in good condition.
Nasr also works with neuro-ophthalmologists to monitor the optic nerve. “From time to time we bring in strabismus specialists to work on correcting the muscles to minimize double vision,” he says.
What should I do if I think I have TED?
Many people attribute their eye problems to aging or allergies, Douglas says. And even when they try to find out what’s wrong, they can be told it’s just allergies. If you notice that your eyes are puffy, your vision changes, or your eyelids don’t close completely, Douglas advises you to see your doctor. “Don’t settle for an unsatisfactory answer,” he says.
Nasr makes it a point to ask all of his patients with autoimmune thyroid disease if their eyes feel dry, uncomfortable, or have pain behind them. “Dry eyes are probably the most common symptom in patients with thyroid eye disease,” he says. But since dryness can be subtle, it can go unnoticed.
If you already have thyroid disease, you should consult an endocrinologist anyway. They will continue to do what they do best: keep your thyroid well controlled. Nasr does a thorough eye exam every year. It uses a special instrument to measure how far the eyeball protrudes. Your endocrinologist may also refer you to another expert for treatment if needed.
Maybe you don’t have a history of thyroid disease. In this case, your best option is to consult an ophthalmologist. They will be able to diagnose PDD. You will also need to have your thyroid levels checked by your GP or an endocrinologist. Indeed, there is a good chance that you also have undiagnosed Graves’ disease.
It’s rare, but you can have PDD with normal thyroid hormone levels. But even if they are normal, you will need to have your levels checked regularly over the next two years. This is because you could develop Graves’ disease during this time.